WOULD you like to eat rat poison? Probably not, but that’s OK, because you’ve eaten it already. Most milk in the United States has rat poison added to it. If you find this disturbing, you can always start reading ingredient lists and don’t buy milk that has rat poison in it. You won’t see “rat poison” as such on the label, however, because manufacturers generally call it by its other name instead.
The other name for rat poison is Vitamin D.
Believe it or not, vitamin D is often used to kill rats. (Not the only chemical used to do that, of course, but a common one.) It’s completely tasteless so rats keep eating bait laced with vitamin D without ever realizing they’re getting hit with a huge huge huge overdose. This might sound bizarre because most of us think of vitamin D as an essential nutrient. And it is. But anything — even an essential nutrient — is potentially toxic if you eat, drink or inhale too much.
I’m often frustrated by the way people talk and think about “chemicals”. I see “chemical-free” products on sale at the supermarket and I wonder what that means. I hear protesters demand that industry stop putting “synthetic chemicals” into our children’s bodies and I wonder if they know what that means or if they know what they’re talking about. Because they think that synthetic chemicals are dangerous, and many of them are. But so is the grilled meat you barbecue on the Fourth of July. Because grilled meat is carcinogenic. I don’t know this for sure, but I suspect it’s probably the second most carcinogenic thing in your home right after the log fire in your fireplace, which (unless you smoke cigarettes or use asbestos) is probably the most carcinogenic thing you have around. Although people don’t realize it, fireplace smoke contains most of the same carcinogens as the fumes from a lit cigarette. But nobody wants to ban grilled meat and log fires, because grilled meat and log fires seem natural. They seem safe.
Which just goes to show how deceptive appearances can be.
Everything is toxic but some things are more toxic than others. You have to drink a lot of water to die of water poisoning, although it’s possible and people have done it. But it doesn’t take a lot of cyanide to send you on your way.
And while it’s true that all chemicals are toxic, it’s also true that some chemicals are necessary or beneficial while others are not. Sure, a massive overdose of water or vitamin D will kill you, but you need both water and vitamin D to stay alive. So water and vitamin D are beneficial at one dose and toxic at another. Cyanide on the other hand is absolutely useless to your system. You don’t need cyanide. Sure, if you just inhale a really really small amount, you’ll live to tell the tale (although I strongly suggest you don’t try this at home). There is, however, no such thing as a “beneficial dose” of cyanide. That’s because water and vitamin D have a role to play in the system of chemical reactions called “your life”. Cyanide, by contrast, does not. It has no normal role in human biochemistry, and in fact it interferes with normal human biochemistry in a very deadly way.
All of which probably makes this concept of “toxic” just seem more mysterious. How can a chemical be deadly at one dose while at another it has no effect (or in the case of useful chemicals like water a beneficial one?) Well, that part gets complicated. But if you want to keep it simple and think about this in a big-picture kind of way, you can boil it down to three reasons ... ► Read the full article in Puff the Mutant Dragon